54 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
or more of the cast chrysalid skins projecting from the stumps of the pin 
oak ; one papa was alive early in April. It is said by Fitch to be more 
common in the Southern and Southwestern States than in the Northern. 
It is also an inhabitant of California, and may be found to occur in 
nearly all the United States wherever the black, red, and white oak or 
locust trees grow. The habits and metamorphoses of the moth were 
first discovered by Peck,* who bred it from caterpillars found in the 
locust, but Harris afterward discovered that it u perforates the trunks 
of the red oak." Bailey states that it also feeds on the willow. (Bull. 
No. 3, Div. Ent., U. S. Dept. Ag., p. 54). 
Riley states that the male caterpillar is only half as large as the 
female. He adds that with her extensile ovipositor the moth deposits 
her eggs in the deep notches and dark bottoms of crevices. u The 
young worms which hatch from them are dark brown with large heads ; 
they are active and commence spinning as soon as they are born n 
(Amer. Ent., II, 127). He finds it more partial in the West to the 
locust than to the oak. 
The following account of its habits and transformations is copied from 
Fitch : 
Of all the wood-boring insects in onr land this is by far the most pernicious, wound- 
ing the trees the most cruelly. The statelies't oaks in our forests are ruined, probably 
in every instance where one of these borers obtains a lodgment in their trunks. It 
perforates a hole the size of a half-inch auger, or large enough to admit the little 
finger, and requiring three or four years for the bark to close together over it. This 
hole running inward to the heart of the tree, and admitting the water thereto from 
every shower that passes, causes a decay in the wood to commence, and the tree never 
regains its previous soundness. t 
This is also a most prolific iusect. The abdomen of the female is so filled and dis- 
tended with eggs that it becomes unwieldy and inert, falling from side to side as its 
position is shifted. A specimen which I once obtained extruded upwards of three 
hundred eggs within a few hours after its capture, its abdomen becoming diminished 
hereby to nearly half its previous bulk ; and in the analogous European species more 
than a thousand eggs have been found on dissection. It hence appears that a single 
one of these insects is capable of ruining a whole forest of oak trees. This calamity, 
however, is prevented, probably by most of the eggs being destroyed, either by birds 
or by other insects, for these borers are by no means so common in our trees as the 
fecundity of their parents would lead us to expect. 
Our moth comes abroad, as already stated, in June and the forepart of July. It dies 
only in the night time, remaining at rest during the day, clinging to the trunks of 
trees, its gray color being so similar to that of the bark that it usually escapes notice. 
In repose its wings are held together in the shape of a roof, covering the hind body. 
From observing her motions in confinement, I think the female does not insert her 
eggs into the bark, but mepely drops them into the cracks and crevices upon its outer 
surface. They are coated with a glutinous matter which immediately dries and 
hardens on exposure to the air, whereby they adhere to the spot where they touch ; 
and if the short two-jointed ovipositor be not fully exserted as the egg is p 
* Mass. Agr. Report and Journal, Vol. v, p. 67, with a plate, 1318. 
t We have observed that the old burrows are lined by a dark layer, consisting of a 
mealy debris about as thick as pasteboard ; this detritus is probably'composed of the 
castings of the larva, which form a paste that in drying strongly adheres to the sides 
of the gallery.— A. S. P. 
